Stair structure.



91 29] W rzken;

w M QMQM Patented Oct. 18,1910.

ALVAH A. GBINEB, OF CHICAGO, ILLINOIS.

BTAIB BTfiUCTUBE.

973,109. fllmllflflon 0! Letters nt atented Oct. 18, 1 910. Application filed December 2, 1809. Serial No. 630,846.

To all whom it may concern: stairs a neat and finished appearance. The

Be it known that I, ALVAH Gnnvrn a citizen of the United States, residing at Clucagofin the county of Cook and State of Illinois, have invented certain new and use ful Im rovements in Stair Structures, of which tlie following is a specification.

My invention relates to an m rovement in the construction of sheet meta StfillS of that type in which the treads oi the stairs are covered with a plastic material, such as concrete- The principal object of my invention comprehends the production of a device of the above character which is ad ustabIe, and of such construction that the risers and treads may be riveted together indlvidually, and the sections formed thereby kept 1n stock in large quantities, ready to be carried to the job and assembled in place on the stair stringers, the adjustment permitting the height of the risers and the length of the treads to be adjusted according to the spec1- ficat-ion of the stairs, as the sections are assembled.

Heretofore in the construction of fire roof stairs it was necessary to cut, and dr' the rivet holes in, the risers and treads for each particular job, and then rivet the same together at the job, but by the use of my mvention' this-will become unn and considerable time will thereby be saved.

In the accompanying drawings which illustrate my invention in its preferred form, and in which like reference numerals indicate corresponding parts throughout the several views-Figure 1 is a vertical longitudinal sectional view of a portiom of a stairs constructed in accordance with my invention, and Fi 2 is a transverse sectional view taken on e line 3-3 of Fig. 1, lookin down.

efereuce being had to the drawings and the reference numerals indicated thereon, 1 indicates a, portion of one of the metal strin rs of the stairs, to the inner side of whic the risers and treads are attached.

The risers are indicated by the numeral 2, and each comprises a sin 1e piece of sheet metal, preferably sheet steel, the upper eggs of which is bent forwardly, then upwar y, and then rearwardly, as at 3, 4, and 5, respectively, so as to form what is commonly termed a nosing. This nosing serves to prevent the edge of the plastic material A from chipping or breaking, and also to give the lower edge of each of the risers is provided with a number of longitudinally arranged slots 6, for a purpose to be hereinafter referred to. The treads 7 are also formed of a single piece of sheet metal and each have their front edge bent upwardly at right angles, as at 8, the upper edge of which isflush with the upper side of the bent )ortion 30f the riser 2. The rear edge of each 0 the treadsis provided with a number of horizontally arranged slots 9 similar to the slots 6 of the risers 2. After the risers and treads have been cut to size and formed as above described, they are rigidly connected together by means of rivets 10 passing through the bent portions 8 of the treads and through the risers 2, and the sections kept in stock ready to be assembled in place on the stair stringers.

The means I employ for uniting the sec tions, comprises an angle bar ll. the horizontal flange of which is adapted to fit a 'ainstthe under sit'le and adjacent the rear edge of the tread 7 of one section, and its vertical flange against the rear side, and adjacent the lower edge of the riser 2 of the next section above said tread. Both flanges of the angle bar 11 are )rovided with holes 12, in alinement with the slots 6 and 9 of the risers and treads respectively. Int-roduced through said holes and working in the slots ('3 and 9 are bolts 13, the threaded ends of which receive clamping nuts 1%. By this arrangement it will be seen that in assembling the sections the treads and risers may be readily adjusted according to the specifications, and by tightening the clam ing nuts 14 they will be ri dly held at th desired adjustment. It w l be noted that these clamping nuts 14 rest against the front faces of the users 2 and the upper faces of the trends 7, so that when the concrete, or other plastic material A, is filled in, said nuts will be embedded therein and are consequently prevented from turning or becoming loose.

The variations in the dimensions of stairs are very slight, and by making the slots (3 and 9 of sufficient. length risers and trends of one size may be used in practically all cases. The risers and trends may be secured to the stringers by means of the rivets 15 passing through tongues 16 formed on the ends of said risers :uul treads and bent. at 110 right angles thereto, and through the string ers. However, if desired, thus-c tongues may r be oliiitted and the risers and treads secured to the stringers by means of the usual angle irons.

W'hile I have shown and described m invention in its preferred form, it wi 1 be understood that various changes may he made without departing from the spirit thereof, and no limitation is im lied by reason of the particular structure s 1own.

I claim:

1. A stair structure comprising aseries of sections, each section embodying u riser and a tread, and means to adj nstably connect the rear edge of the tread of one section to the lower edge of the riser of the next section thereabove.

2. A. stair structure, comprising a series of sect-ions, each section comprising a riser and a tread, slots formed in said risers adjacenttheir lower edges, and in said treads adjacent their ren r edges, and means for adjustably connecting the rear edge of the trend of one section to the lower edge of the riser of the next section above having elements to engage in said slots.

A stair structure, comprising a series of sections, each section comprising a riser and a tread, slots formed in said risers adjacent the lower edges, and in said treads adjacent their rear edges, angle bars connecting the trend of one section to the riser of the next section above, and bolts passing through the flanges of said angle bins and working in the aforesaid slots, and provided with clamping nuts, whereby the sections may be adjnsted.

In testimony whereof I afiix my signature in presence of two witnesses.

ALVAH A. GRINER.

Vitnesses FRANK H. T. Po'rnln, An'rnun \VrsLsY. 

